Leaching of phthalate esters from different drinking stuffs and their subsequent biodegradation

Phthalate esters (PAEs) are mainly used as plasticizers, and their release in the environment during the manufacturing, use, and disposal has caused serious environmental health concerns, since some of them are suspected to be mutagens, hepatotoxic agents, and carcinogens. In the present study, leaching of PAEs from different drinking stuffs (water cooler, mineral water bottles) exposed to sunlight and baby feeders subjected to different heating treatments (boiling, autoclave and oven) was studied. Results showed that a total of 10 PAEs were leached and identified. Among them, dimethyl phthalate, bis(2-methoxyethyl) phthalate, diethyl phthalate, and dibutyl phthalate were the major leached PAEs found in the range 9-112.50 mu g L-1. Boiling treatment was found safer for baby feeders as PAE leaching was similar to 26-54% less as compared to other two treatments. The leached PAEs in water samples were then subjected to biodegradation experiment with Bacillus thuringiensis strain at optimized conditions (time 72 h and 30 degrees C). Hence, leaching of hazardous PAEs from different water stuffs is alarming and needs immediate attention. Moreover, B. thuringiensis strain was found effective for PAE remediation (75-96% degradation) at neutral pH.